Rearchers at Stanford University have found a way to move muscles with pulses of light. The study, published in Nature Medicine, describes what the researchers are calling “optogenetics” — a technology which uses light-sensitive proteins from a single-celled alga placed on the nerve and pulses of light to trigger muscle movement. The researchers insert the gene for a protein called channelrhodopsin-2, which comes from green algae. Then when the neuron implanted with the gene is exposed to blue light, the protein starts a chain of electrical activity inside the cell which spreads to surrounding neurons.